The carcass reinforcement of tires is currently constituted by one or more plies, most frequently radial ones, which are turned up about one or more bead wires arranged in the beads. This turning-up of the ply around the bead wire constitutes the means making it possible to fix or anchor the ply in the bead.
However, there are nowadays tires which do not have the conventional upturn of the carcass ply around a bead wire, or even a bead wire, in the conventional sense of this element. For example, document EP 0 582 196 describes a manner of arranging a reinforcement structure of carcass type in the beads, by arranging adjacent to said reinforcement structure circumferential filaments, the whole being embedded in an anchoring or bonding rubber mix, preferably of high elasticity modulus. Several arrangements are proposed in this document. Generally, the spacing or distance between the circumferential cords and the carcass-type reinforcement structure is substantially constant along the entire anchoring zone. Thus, the taking up, by the circumferential cords, of the forces induced by the reinforcement structure takes place first and foremost and in a major part by the circumferential cords located radially internally. There is then less force to be recovered by the other circumferential cords of the anchoring zone.
Furthermore, one and the same distance is observed between the circumferential cords and the carcass-type reinforcement structure both in the radially inner portion, in which the movements are limited, and in the radially outer portion, where the movements or displacements are greater due to the displacement of the sidewall towards the outside under the action of the pressure or the forces induced for example when cornering.